package com.imooc.util;

import org.springframework.beans.BeansException;
import org.springframework.beans.factory.NoSuchBeanDefinitionException;
import org.springframework.beans.factory.config.BeanFactoryPostProcessor;
import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
import org.springframework.stereotype.Component;

/**
 * spring工具类 方便在非spring管理环境中获取bean
 */
@SuppressWarnings("unchecked")
@Component
public class SpringUtil implements BeanFactoryPostProcessor {

    /**
     * Spring应用上下文环境
     */
    private static ConfigurableListableBeanFactory beanFactory;

    @Override
    public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
        SpringUtil.beanFactory = beanFactory;
    }

    /**
     * 获取对象
     */
    public static <T> T getBean(String beanName) {
        return (T) beanFactory.getBean(beanName);
    }

    /**
     * 获取对象
     */
    public static <T> T getBean(Class<T> clz) throws BeansException {
        return beanFactory.getBean(clz);
    }

    /**
     * 如果BeanFactory包含一个与所给名称匹配的bean定义，则返回true
     */
    public static boolean containsBean(String name) {
        return beanFactory.containsBean(name);
    }

    /**
     * 判断以给定名字注册的bean定义是一个singleton还是一个prototype。
     */
    public static boolean isSingleton(String name) throws NoSuchBeanDefinitionException {
        return beanFactory.isSingleton(name);
    }

    /**
     * 注册对象的类型
     */
    public static Class<?> getType(String name) throws NoSuchBeanDefinitionException {
        return beanFactory.getType(name);
    }

    /**
     * 如果给定的bean名字在bean定义中有别名，则返回这些别名
     */
    public static String[] getAliases(String name) throws NoSuchBeanDefinitionException {
        return beanFactory.getAliases(name);
    }
}
